In vitro regeneration of sugar palm (Arenga pinnata Wurmb Merr.)

Abstract

Optimization of a protocol for in vitro regeneration of sugar palm (Arenga pinnata Wurmb Merr.) by direct organogenesis using the immature zygotic embryo and basal stem explants of in vitro raised seedlings has been developed. The explants were cultured on MS medium supplemented with different concentrations of PGRs, and the organogenic capability of the explants was investigated. Both explants were responsive, but the results were greatly dependent on the genotype and the culture medium composition investigated. After 8 weeks of culture, basal stem explant cultured on MS + 1.0 mg/L Kin + 2.0 mg/L NAA promoted optimum response for direct organogenesis (90%) with a total of 9 adventitious shoots and 25 roots. Subculturing of individual shoots in basal MS medium (MS0) optimized further development. Meanwhile, immature zygotic embryo explant cultured on MS + 2.0 mg/L BAP + 2.0 mg/L NAA promoted optimum root regeneration (70%), though MS medium containing 2.0 mg/L BAP + 1.0 mg/L GA3 and 1.0 mg/L AgNO3 promoted optimum shoots growth (total of 10 shoots) at the rate of 0.04%. In vitro rooting of the regenerated shoots was successfully obtained on MS + 3.0 mg/L IBA. Established in vitro plantlets with roots were hardened in soil: peat moss: perlite (2:2:1) mixture. Acclimatization of plantlets was successfully obtained with 70% seedlings survived after 4 month's exposures under the light intensity of 50-100 μmol m-2s-1.